243266409 has 15 divisors (see below), whose sum is σ = 363607783. Its totient is φ = 162084024.

The previous prime is 243266363. The next prime is 243266503. The reversal of 243266409 is 904662342.

The square root of 243266409 is 15597.

It is a perfect power (a square), and thus also a powerful number.

243266409 is a `hidden beast` number, since 2 + 4 + 3 + 2 + 6 + 640 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 108056025 + 135210384 = 10395^2 + 11628^2 .

It is not a de Polignac number, because 243266409 - 2¹³ = 243258217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (243266509) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 139507 + ... + 141239.

Almost surely, 2^243266409 is an apocalyptic number.

243266409 is the 15597-th square number.

243266409 is the 7799-th centered octagonal number.

It is an amenable number.

243266409 is a deficient number, since it is larger than the sum of its proper divisors (120341374).

243266409 is an frugal number, since it uses more digits than its factorization.

243266409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3478 (or 1736 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The cubic root of 243266409 is about 624.2531101511.

Multiplying 243266409 by its sum of digits (36), we get a square (8757590724 = 93582²).

The spelling of 243266409 in words is "two hundred forty-three million, two hundred sixty-six thousand, four hundred nine".